HPLC法同时测定苹果及浓缩苹果汁中吡虫清等4种农药的残留量

Determination of residual carbendazim,thiabendazile,imidacloprid and acetamiprid in apple and apple juice concentrate by HPLC

建立了反相高效液相色谱-双波长检测法同时测定苹果及浓缩苹果汁中多菌灵、噻菌灵、吡虫啉、吡虫清4种农药残留量的方法。苹果样品经乙腈提取，加水稀释，而浓缩苹果汁样品直接用体积分数20％乙腈稀释后，利用CH2Cl2液-液萃取净化。分析时用C18色谱柱分离，以乙腈-0．05％冰乙酸系统梯度洗脱，选择246nm和280nm双波长检测。该方法4种农药的线性关系良好（r≥0．9999），检出限均为0．002mg/kg，加标回收率在84．3％～109．1％范围内，相对标准偏差为2．0％～5．4％。本方法能够满足农药残留检测要求。

A method was developed for the determination of residual carbendazim, thiabendazole, imidacloprid and acetamiprid in apple and apple juice concentrate by HPLC under double UV wavelengths. Apple samples were extracted with acetonitrile and diluted with water, and apple juice concentrate samples were diluted with 20% acetonitrile, then clean-up was performed on liquid-liquid partitioning after addition of dichlormethane. HPLC was performed on a C18 column with DAD detection! at 346 nm and 280 nm using a gradient solvent system （acetonitrile- 0.05% acetic acid）. The presented method showed good linear relationship （r ≥0. 9999） with good precision and accuracy for the four pesticides, the detection limits were all 0.002 mg/kg, the recoveries ranged from 84.3% to 109.1% with relative standard deviations between 2.0% and 5.4%. The method is fast, sufficient, simple for the pesticide residue analysis.